U.S. patent application number 15/313456 was filed with the patent office on 2017-07-06 for propylene-based polymer composition.
This patent application is currently assigned to BASELL POLIOEFINE ITALIA S.R.L.. The applicant listed for this patent is BASELL POLIOEFINE ITALIA S.R.L.. Invention is credited to TIZIANA CAPUTO, MARCO CIARAFONI, NICOLETTA MARTINI, PAOLA MASSARI.
Application Number | 20170190893 15/313456 |
Document ID | / |
Family ID | 50819648 |
Filed Date | 2017-07-06 |
United States Patent
Application |
20170190893 |
Kind Code |
A1 |
MASSARI; PAOLA ; et
al. |
July 6, 2017 |
PROPYLENE-BASED POLYMER COMPOSITION
Abstract
A propylene polymer composition comprising: A) from 81 wt % to
91 wt % of a propylene ethylene copolymer containing from 1.0 wt %
to 3.5 wt % of ethylene derived units having a fraction soluble in
xylene at 25.degree. C. comprised between 10 wt % and 3 wt %; and a
melt flow rate ranging from 5 to 50 g/10 min; B) from 9 wt % to 19
wt %, of a copolymer of propylene and ethylene with from 21.0 wt %
to 31.0 wt % of ethylene derived units; the sum A)+B) being 100;
the composition having an melt flow rate ranging from 20 to 35 g/10
min; the xylene soluble fraction to 25.degree. C. ranging from 13.0
wt % to 25.0 wt % and the intrinsic viscosity of the fraction
soluble in xylene at 25.degree. C. ranging from 0.7 dl/g to 1.9
dl/g.
Inventors: |
MASSARI; PAOLA; (FERRARA,
IT) ; CIARAFONI; MARCO; (FERRARA, IT) ;
CAPUTO; TIZIANA; (FERRARA, IT) ; MARTINI;
NICOLETTA; (FERRARA, IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BASELL POLIOEFINE ITALIA S.R.L. |
MILANO |
|
IT |
|
|
Assignee: |
BASELL POLIOEFINE ITALIA
S.R.L.
MILANO
IT
|
Family ID: |
50819648 |
Appl. No.: |
15/313456 |
Filed: |
April 28, 2015 |
PCT Filed: |
April 28, 2015 |
PCT NO: |
PCT/EP2015/059239 |
371 Date: |
November 22, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08L 23/142 20130101;
C08L 23/16 20130101; C08L 2207/02 20130101; C08L 23/142 20130101;
C08L 2205/025 20130101; C08L 2205/025 20130101; C08L 23/16
20130101; C08L 23/16 20130101; C08L 23/142 20130101; C08L 2205/02
20130101 |
International
Class: |
C08L 23/14 20060101
C08L023/14; C08L 23/16 20060101 C08L023/16 |
Foreign Application Data
Date |
Code |
Application Number |
May 28, 2014 |
EP |
14170323.1 |
Claims
1. A propylene polymer composition comprising: A) from 81 wt % to
91 wt % of a propylene ethylene copolymer containing from 1.0 wt %
to 3.5 wt % of ethylene derived units having a fraction soluble in
xylene at 25.degree. C. comprised between 10 wt % and 3 wt %; and a
melt flow rate (MFR L according to ISO 1133, condition L,
230.degree. C. and 2.16 kg load) ranging from 5 to 50 g/10 min; B)
from 9 wt % to 19 wt %, of a copolymer of propylene and ethylene
with from 21.0 wt % to 31.0 wt % of ethylene derived units; the sum
A)+B) being 100; the composition having an melt flow rate (MFR L
according to ISO 1133, condition L, i.e. 230.degree. C. and 2.16 kg
load) ranging from 20 to 35 g/10 min; the xylene soluble fraction
to 25.degree. C. ranging from 10.0 wt % to 25.0 wt % and the
intrinsic viscosity of the fraction soluble in xylene at 25.degree.
C. ranging from 0.7 dl/g to 1.9 dl/g.
2. The propylene polymer composition according to claim 1,
comprising: A) from 83 wt % to 89 wt %, of component A); B) from 11
wt % to 17 wt %, of component B);
3. The propylene polymer composition according to claim 1 wherein
the propylene ethylene copolymer A) contains from 1.5 wt % to 3.0
wt % of ethylene derived units.
4. The propylene polymer composition according to claim 1 wherein
the propylene ethylene copolymer B) contains from 23.0 wt % to 29.0
wt %, of ethylene derived units.
5. The propylene polymer composition according to claim 1 wherein
the polyolefin composition has MFR L (Melt Flow Rate according to
ISO 1133, condition L, i.e. 230.degree. C. and 2.16 kg load)
comprised between from 22 to 32 g/10 min.
6. The propylene polymer composition according to claim 1 wherein
the intrinsic viscosity of the fraction soluble in xylene at
25.degree. C. ranges from 0.9 dl/g to 1.4 dl/g.
7. (canceled)
8. The propylene polymer composition according to claim 1 wherein
the propylene polymer composition is not visbroken.
9. The propylene polymer composition according to claim 2 wherein
the propylene ethylene copolymer A) contains from 1.5 wt % to 3.0
wt % of ethylene derived units.
Description
FIELD OF THE INVENTION
[0001] The present disclosure relates to a propylene-based polymer
composition having a high melt flow rate for injection molding for
the production of containers, particularly containers for food.
BACKGROUND OF THE INVENTION
[0002] Polyolefins may be used to produce injection molded articles
and containers for food products. Polypropylene heterophasic
compositions, due to their impact resistance properties that extend
at low temperatures, can be used in the production of containers
for frozen food products. While polymers for the injection molding
may have a a high melt flow rate (MFR), the high MFR can be
detrimental for some mechanical and optical properties.
[0003] WO 2006/114357 relates to a propylene polymer composition
comprising (weight percentages being referred to the sum of
A+B):
[0004] (A) 60-90% by weight of a copolymer of propylene with
ethylene containing less than 2.5% wt of ethylene units; and
[0005] (B) 10-40% by weight of a copolymer of propylene comprising
from 15 to 35% wt of ethylene units,
[0006] said polymer composition having a melt flow rate value
according to ISO 1133 (230.degree. C., 2.16 Kg) of less than 10
g/10 min
[0007] Even if these compositions show good values of Haze and Izod
the MFR may be too low to be used in injection molding.
[0008] US 2004/0266952 relates to a propylene polymer composition
comprising (percent by weight):
[0009] A) from 50 to 90% of one or more propylene copolymer(s)
having a content of moiety insoluble in xylene at room temperature
of not less than 85%, selected from the group consisting of (A1)
random copolymers of propylene with ethylene containing from 1 to
of ethylene; (A2) copolymers of propylene with one or more C4-C8
a-olefin(s) containing 2-10% of the C4-C8 a-olefin(s); and (A3)
copolymers of propylene with ethylene and one or more C4-C8
a-olefin(s) containing 0.5-5% of ethylene and 2-6% of C4-C8
a-olefins; and
[0010] B) from 10 to 50% of a copolymer of propylene containing
from 8 to 40% of ethylene and optionally 1-10% of a C4-C8
a-olefins;
[0011] wherein the propylene polymer composition has an MFR (2)
value of from 3 to 30 g/10 min obtained by subjecting to
degradation a precursor composition comprising the same copolymers
(a) and (b) in the above said proportions having an MFR (1) value
of from 0.1 to 5 g/10 min, with a ratio MFR (2) to MFR (1) of from
1.5 to 20.
[0012] In the examples the value of impact properties of the
visbroken polymer may be high, however, the haze measured on a film
may be low.
[0013] The applicant found a propylene polymer composition
containing propylene and ethylene having an high MFR can be
fine-tuned in order to achieve an optimum balance of mechanical and
optical properties for the production of injection molded articles,
such as containers.
SUMMARY OF THE INVENTION
[0014] An object of the present disclosure is a propylene polymer
composition comprising:
[0015] A) from 81 wt % to 91 wt %, of a propylene ethylene
copolymer containing from 1.0 wt % to 3.5 wt % of ethylene derived
units having a fraction soluble in xylene at 25.degree. C.
comprised between 10 wt % and 3 wt %; and a melt flow rate (MFR L
according to ISO 1133, condition L, i.e. 230.degree. C. and 2.16 kg
load) ranging from 5 to 50 g/10 min;
[0016] B) from 9 wt % to 19 wt %, of a copolymer of propylene and
ethylene with from 21.0 wt % to 31.0 wt %, of ethylene derived
units;
[0017] the sum A)+B) being 100;
[0018] the composition having an melt flow rate (MFR L according to
ISO 1133, condition L, i.e. 230.degree. C. and 2.16 kg load)
ranging from 20 to 35 g/10 min; the xylene soluble fraction to
25.degree. C. ranging from 10.0 wt % to 25.0 wt % and the intrinsic
viscosity of the fraction soluble in xylene at 25.degree. C.
ranging from 0.7 dl/g to 1.9 dl/g.
DETAILED DESCRIPTION OF THE INVENTION
[0019] An object of the present disclosure is a propylene polymer
composition comprising:
[0020] A) from 81 wt % to 91 wt %, alternatively from 82 wt % to 90
wt %, alternatively from 83 wt % to 89 wt %, of a propylene
ethylene copolymer containing from 1.0 wt % to 3.5 wt %,
alternatively from 1.5 wt % to 3.0 wt % of ethylene derived units
having a fraction soluble in xylene at 25.degree. C. comprised
between 10 wt % and 3 wt %; alternatively between 8 wt % and 4 wt %
and a melt flow rate (MFR L according to ISO 1133, condition L,
i.e. 230.degree. C. and 2.16 kg load) ranging from 5 to 50 g/10 min
including from 10 to 40 g/10 min and from 15 to 30 g/10 min;
[0021] B) from 9 wt % to 19 wt %, alternatively from 10% to 18 wt %
or from 11 wt % to 17 wt % of a copolymer of propylene and ethylene
with from 21.0 wt % to 31.0 wt %, alternatively from 23.0 wt % to
29.0 wt %, or from 25.0 wt % to 28.0 wt %; of ethylene derived
units;
[0022] the sum A)+B) being 100;
[0023] the composition having an melt flow rate (MFR L according to
ISO 1133, condition L, i.e. 230.degree. C. and 2.16 kg load)
ranging from 20 to 35 g/10 min, alternatively from 22 to 32 g/10
min or from 24 to 29 g/10 min; the xylene soluble fraction to
25.degree. C. ranging from 10.0 wt % to 25.0 wt % alternatively
from 13.0 wt % to 20.0 wt % or from 16.0 wt % to 19 wt % and the
intrinsic viscosity of the fraction soluble in xylene at 25.degree.
C. ranging from 0.7 dl/g to 1.9 dl/g, or alternatively from 0.9
dl/g to 1.4 dl/g.
[0024] For the purpose of the present disclosure the term
"copolymer" includes polymers containing only propylene and
ethylene monomers.
[0025] The propylene polymer composition according to the present
disclosure is may not be visbroken.
[0026] For the purpose of the present disclosure the term
"container" means any kind of object able to contain liquid or
solid matter. Said container may have one or more bottom parts,
optionally one or more top parts and one or more lateral walls. The
lateral walls and the bottom and top part (when present) may have a
thickness ranging from 0.1 mm to 5 mm, alternatively from 0.2 mm to
3 mm or from 0.3 mm to 2 mm. Examples are containers for ice cream,
eggs, yoghurt, fish and frozen fish.
[0027] The MFR of the polyolefin composition to be used for
obtaining the container object of the present disclosure can be
obtained directly as ex-reactor polymer, i.e. with one or more
polymerization step, and not by blending components A) and B),
optionally with the addition of additives but without alteration of
its chemical structure by any treatment such as radiation treatment
or chemical degradation, such as visbreaking. This allows for a
material having a desirable MFR but without the drawback of the
degraded polymers,
[0028] Materials that can be used in injection molding processes
may have a high MFR to allow the polymer to be easily injected in
the mold. However, a high MFR polymers may not have satisfactory
mechanical and optical properties. The balance of the various
parameters of the propylene polymer composition of the present
disclosure such as ethylene content, split (amount of component A
and B), MFR and intrinsic viscosity allows for a material that can
be used in order to obtain injection molded articles, including but
not limited to containers.
[0029] The propylene polymer composition fit for the production of
the container according to the present disclosure may possess a
flexural modulus ranging from 700 MPa to 1100 MPa or alternatively
from 750 MPa and 1000 MPa.
[0030] The polyolefin composition of the present disclosure can be
prepared by sequential polymerization in at least two stages, with
each subsequent polymerization stage being conducted in the
presence of the polymeric material formed in the immediately
preceding polymerization reaction, wherein the component (A) is
prepared in at least one first polymerization stage and the
component (B) is prepared in at least one second polymerization
stage.
[0031] Each polymerization stage is carried out in presence of a
highly stereospecific heterogeneous Ziegler-Natta catalyst. The
Ziegler-Natta catalysts producing the propylene polymer
compositions of the present disclosure comprise a solid catalyst
component comprising at least one titanium compound having at least
one titanium-halogen bond and at least an electron-donor compound
(internal donor), both supported on magnesium chloride. The
Ziegler-Natta catalysts systems further may comprise an
organo-aluminum compound as a co-catalyst and optionally an
external electron-donor compound.
[0032] Catalysts systems are described in the European patents
EP45977, EP361494, EP728769, EP 1272533 and in the international
patent application WO00163261.
[0033] The propylene polymer of the present disclosure may be
obtained by polymerizing propylene and ethylene in various stages
in the presence of a catalyst system comprising the product
obtained by contacting the following components:
[0034] (a) a solid catalyst component comprising a magnesium
halide, a titanium compound having at least a Ti-halogen bond and
at least two electron donor compounds one of which being present in
an amount from 40 to 90% by mol with respect to the total amount of
donors and selected from succinates and the other being selected
from 1,3 diethers,
[0035] (b) an aluminum hydrocarbyl compound, and
[0036] (c) optionally an external electron donor compound.
[0037] In the solid catalyst component (a) the succinate may be
selected from succinates of formula (I)
##STR00001##
[0038] in which the substituent groups R.sup.1 and R.sup.2, may be
equal to, or different from, each other are a C.sub.1-C.sub.20
linear or branched alkyl, alkenyl, cycloalkyl, aryl, arylalkyl or
alkylaryl group, optionally containing heteroatoms; and the
substituent groups R.sup.3 and R.sup.4 may be equal to, or
different from, each other, are C.sub.1-C.sub.20 alkyl,
C.sub.3-C.sub.20 cycloalkyl, C.sub.5-C.sub.20 aryl, arylalkyl or
alkylaryl group with the proviso that at least one of the
substituent groups is a branched alkyl; said compounds being, with
respect to the two asymmetric carbon atoms identified in the
structure of formula (I), stereoisomers of the type (S,R) or
(R,S)
[0039] R.sup.1 and R.sup.2 may be C.sub.1-C.sub.8 alkyl,
cycloalkyl, aryl, arylalkyl and alkylaryl groups, and R.sup.1 and
R.sup.2 substituent groups selected from primary alkyls and
branched primary alkyls may be desired. Examples of R.sup.1 and
R.sup.2 groups can be methyl, ethyl, n-propyl, n-butyl, isobutyl,
neopentyl, 2-ethylhexyl.
[0040] Compounds in which the R.sup.3 and/or R.sup.4 substituent
groups are secondary alkyls like isopropyl, sec-butyl, 2-pentyl,
3-pentyl or cycloakyl s like cyclohexyl, cyclopentyl,
cyclohexylmethyl may be desired as well.
[0041] Examples of the above-mentioned compounds are the (S,R)
(S,R) forms pure or in mixture, optionally in racemic form, of
diethyl 2,3-bis(trimethylsilyl)succinate, diethyl
2,3-bis(2-ethylbutyl)succinate, diethyl 2,3-dibenzylsuccinate,
diethyl 2,3-diisopropylsuccinate, diisobutyl 2,3-diisopropyl
succinate, diethyl 2,3-bis(cyclohexylmethyl)succinate, diethyl
2,3-diisobutylsuccinate, diethyl 2,3-dineopentylsuccinate, diethyl
2,3-dicyclopentylsuccinate, diethyl 2,3-dicyclohexylsuccinate.
[0042] Among the 1,3-diethers mentioned above, compounds of formula
(II) may include compounds
##STR00002##
[0043] where R.sup.I and R.sup.II may be the same or different and
may be hydrogen or linear or branched C.sub.1-C.sub.18 hydrocarbon
groups which can also form one or more cyclic structures; R.sup.III
groups, may be equal or different from each other, may be hydrogen
or C.sub.1-C.sub.18 hydrocarbon groups; R.sup.IV groups may be
equal or different from each other, have the same meaning of
R.sup.III except that these substituent groups cannot be hydrogen;
each of R.sup.I to R.sup.IV groups can contain heteroatoms selected
from halogens, N, O, S and Si.
[0044] R.sup.IV may be a 1-6 carbon atom alkyl radical and more
particularly a methyl while the R.sup.III radicals may be hydrogen.
Moreover, when R.sup.I is methyl, ethyl, propyl, or isopropyl,
R.sup.II can be ethyl, propyl, isopropyl, butyl, isobutyl,
tert-butyl, isopentyl, 2-ethylhexyl, cyclopentyl, cyclohexyl,
methylcyclohexyl, phenyl or benzyl; when R.sup.I is hydrogen,
R.sup.II can be ethyl, butyl, sec-butyl, tert-butyl, 2-ethylhexyl,
cyclohexylethyl, diphenylmethyl, p-chlorophenyl, 1-naphthyl,
1-decahydronaphthyl; RI and RII can also be the same and can be
ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, neopentyl,
phenyl, benzyl, cyclohexyl, cyclopentyl.
[0045] Specific examples of ethers that can be used include:
2-(2-ethylhexyl)1,3-dimethoxypropane,
2-isopropyl-1,3-dimethoxypropane, 2-butyl-1,3-dimethoxypropane,
2-sec-butyl-1,3-dimethoxypropane,
2-cyclohexyl-1,3-dimethoxypropane, 2-phenyl-1,3-dimethoxypropane,
2-tert-butyl-1,3-dimethoxypropane, 2-cumyl-1,3-dimethoxypropane,
2-(2-phenylethyl)-1,3-dimethoxypropane,
2-(2-cyclohexylethyl)-1,3-dimethoxypropane,
2-(p-chlorophenyl)-1,3-dimethoxypropane,
2-(diphenylmethyl)-1,3-dimethoxypropane,
2(1-naphthyl)-1,3-dimethoxypropane,
2(p-fluorophenyl)-1,3-dimethoxypropane,
2(1-decahydronaphthyl)-1,3-dimethoxypropane,
2(p-tert-butylphenyl)-1,3-dimethoxypropane,
2,2-dicyclohexyl-1,3-dimethoxypropane,
2,2-diethyl-1,3-dimethoxypropane,
2,2-dipropyl-1,3-dimethoxypropane,
2,2-dibutyl-1,3-dimethoxypropane, 2,2-diethyl-1,3-diethoxypropane,
2,2-dicyclopentyl-1,3-dimethoxypropane,
2,2-dipropyl-1,3-diethoxypropane, 2,2-dibutyl-1,3-diethoxypropane,
2-methyl-2-ethyl-1,3-dimethoxypropane,
2-methyl-2-propyl-1,3-dimethoxypropane,
2-methyl-2-benzyl-1,3-dimethoxypropane,
2-methyl-2-phenyl-1,3-dimethoxypropane,
2-methyl-2-cyclohexyl-1,3-dimethoxypropane,
2-methyl-2-methylcyclohexyl-1,3-dimethoxypropane,
2,2-bis(p-chlorophenyl)-1,3-dimethoxypropane,
2,2-bis(2-phenylethyl)-1,3-dimethoxypropane,
2,2-bis(2-cyclohexylethyl)-1,3-dimethoxypropane,
2-methyl-2-isobutyl-1,3-dimethoxypropane,
2-methyl-2-(2-ethylhexyl)-1,3-dimethoxypropane,
2,2-bis(2-ethylhexyl)-1,3-dimethoxypropane,
2,2-bis(p-methylphenyl)-1,3-dimethoxypropane,
2-methyl-2-isopropyl-1,3-dimethoxypropane,
2,2-diisobutyl-1,3-dimethoxypropane,
2,2-diphenyl-1,3-dimethoxypropane,
2,2-dibenzyl-1,3-dimethoxypropane,
2-isopropyl-2-cyclopentyl-1,3-dimethoxypropane,
2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane,
2,2-diisobutyl-1,3-diethoxypropane,
2,2-diisobutyl-1,3-dibutoxypropane,
2-isobutyl-2-isopropyl-1,3-dimetoxypropane,
2,2-di-sec-butyl-1,3-dimetoxypropane,
2,2-di-tert-butyl-1,3-dimethoxypropane,
2,2-dineopentyl-1,3-dimethoxypropane,
2-iso-propyl-2-isopentyl-1,3-dimethoxypropane,
2-phenyl-2-benzyl-1,3-dimetoxypropane,
2-cyclohexyl-2-cyclohexylmethyl-1,3-dimethoxypropane.
[0046] Furthermore, the 1,3-diethers of formula (III) may
include
##STR00003##
[0047] where the substituent group R.sup.IV has the same meaning
explained above and the substituent groups R.sup.III and R.sup.V,
may be equal or different to each other, and selected from the
group consisting of hydrogen; halogens, including Cl and F;
C.sub.1-C.sub.20 alkyl groups, linear or branched; C.sub.3-C.sub.20
cycloalkyl, C.sub.6-C.sub.20 aryl, C.sub.7-C.sub.20 alkaryl and
C.sub.7-C.sub.20 aralkyl and two or more of the R.sup.V can be
bonded to each other to form condensed cyclic structures, saturated
or unsaturated, optionally substituted with R.sup.VI selected from
the group consisting of halogens, including Cl and F; C1-C20 alkyl
groups, linear or branched; C.sub.3-C.sub.20 cycloalkyl,
C.sub.6-C.sub.20 aryl, C.sub.7-C.sub.20 alkaryl and
C.sub.7-C.sub.20 aralkylgroups; said substituent groups R.sup.V and
R.sup.VI optionally containing one or more heteroatoms as
substitutes for carbon or hydrogen atoms, or both.
[0048] In the 1,3-diethers of formulae (I) and (II) the R.sup.III
radicals may be hydrogen, and the R.sup.IV radicals may be methyl.
Moreover, the 1,3-diethers of formula (II) in which two or more of
the R.sup.V substituent groups can be bonded to each other to form
one or more condensed cyclic structures, including benzenic,
optionally substituted by R.sup.VI substituent groups, may be
desired. The compounds of formula (IV) include:
##STR00004##
[0049] where the R.sup.VI may be equal or different are hydrogen;
halogens, including Cl and F; C.sub.1-C.sub.20 alkyl groups, linear
or branched; C.sub.3-C.sub.20 cycloalkyl, C.sub.6-C.sub.20 aryl,
C.sub.7-C.sub.20 alkylaryl and C.sub.7-C.sub.20 aralkyl groups,
optionally containing one or more heteroatoms selected from the
group consisting of N, O, S, P, Si and halogens, including Cl and
F, as substitutes for carbon or hydrogen atoms, or both;
[0050] and R.sup.IV may be as defined above for formula (II).
[0051] Specific examples of compounds comprised in formulae (II)
and (III) are: [0052] 1,1-bis(methoxymethyl)-cyclopentadiene;
[0053] 1,1-bis(methoxymethyl)-2,3,4,5-tetramethylcyclopentadiene;
[0054] 1,1-bis(methoxymethyl)-2,3,4,5-tetraphenylcyclopentadiene;
[0055] 1,1-bis(methoxymethyl)-2,3,4,5-tetrafluorocyclopentadiene;
[0056] 1,1-bis(methoxymethyl)-3,4-dicyclopentylcyclopentadiene;
[0057] 1,1-bis(methoxymethyl)indene;
1,1-bis(methoxymethyl)-2,3-dimethylindene; [0058]
1,1-bis(methoxymethyl)-4,5,6,7-tetrahydroindene; [0059]
1,1-bis(methoxymethyl)-2,3,6,7-tetrafluoroindene; [0060]
1,1-bis(methoxymethyl)-4,7-dimethylindene; [0061]
1,1-bis(methoxymethyl)-3,6-dimethylindene; [0062]
1,1-bis(methoxymethyl)-4-phenylindene; [0063]
1,1-bis(methoxymethyl)-4-phenyl-2-methylindene; [0064]
1,1-bis(methoxymethyl)-4-cyclohexylindene; [0065]
1,1-bis(methoxymethyl)-7-(3,3,3-trifluoropropyl)indene; [0066]
1,1-bis(methoxymethyl)-7-trimethyisilylindene; [0067]
1,1-bis(methoxymethyl)-7-trifluoromethylindene; [0068]
1,1-bis(methoxymethyl)-4,7-dimethyl-4,5,6,7-tetrahydroindene;
[0069] 1,1-bis(methoxymethyl)-7-methylindene; [0070]
1,1-bis(methoxymethyl)-7-cyclopenthylindene; [0071]
1,1-bis(methoxymethyl)-7-isopropylindene; [0072]
1,1-bis(methoxymethyl)-7-cyclohexylindene; [0073]
1,1-bis(methoxymethyl)-7-tert-butylindene; [0074]
1,1-bis(methoxymethyl)-7-tert-butyl-2-methylindene; [0075]
1,1-bis(methoxymethyl)-7-phenylindene; [0076]
1,1-bis(methoxymethyl)-2-phenylindene; [0077]
1,1-bis(methoxymethyl)-1H-benz[e]indene; [0078]
1,1-bis(methoxymethyl)-1H-2-methylbenz[e]indene; [0079]
9,9-bis(methoxymethyl)fluorene; [0080]
9,9-bis(methoxymethyl)-2,3,6,7-tetramethylfluorene; [0081]
9,9-bis(methoxymethyl)-2,3,4,5,6,7-hexafluorofluorene; [0082]
9,9-bis(methoxymethyl)-2,3-benzofluorene; [0083]
9,9-bis(methoxymethyl)-2,3,6,7-dibenzofluorene; [0084]
9,9-bis(methoxymethyl)-2,7-diisopropylfluorene; [0085]
9,9-bis(methoxymethyl)-1,8-dichlorofluorene; [0086]
9,9-bis(methoxymethyl)-2,7-dicyclopentylfluorene; [0087]
9,9-bis(methoxymethyl)-1,8-difluorofluorene; [0088]
9,9-bis(methoxymethyl)-1,2,3,4-tetrahydrofluorene; [0089]
9,9-bis(methoxymethyl)-1,2,3,4,5,6,7,8-octahydrofluorene; [0090]
9,9-bis(methoxymethyl)-4-tert-butylfluorene.
[0091] As explained above, the catalyst component (a) comprises, in
addition to the above electron donors, a titanium compound having
at least a Ti-halogen bond and a Mg halide. The magnesium halide
may be MgCl2 in active form as a support for Ziegler-Natta
catalysts. U.S. Pat. No. 4,298,718 and U.S. Pat. No. 4,495,338
describe the use of these compounds in Ziegler-Natta catalysis.
Magnesium dihalides in active form used as support or co-support in
components of catalysts for the polymerization of olefins may be
characterized by X-ray spectra in which the intensity of
diffraction lines that appear in the spectrum of the non-active
halide may be diminished in intensity and replaced by a halo whose
maximum intensity may be displaced towards lower angles relative to
that of the more intense line.
[0092] Titanium compounds used in the catalyst component of the
present disclosure can be TiCl4 and TiCl3; furthermore, also
Ti-haloalcoholates of formula Ti(OR)n-yXy can be used, where n is
the valence of titanium, y is a number between 1 and n-1 X is
halogen and R is a hydrocarbon radical having from 1 to 10 carbon
atoms.
[0093] The catalyst component (a) has an average particle size
ranging from 15 to 80 .mu.m, alternatively from 20 to 70 .mu.m or
from 25 to 65 .mu.m. As explained the succinate may be present in
an amount ranging from 40 to 90% by mol with respect to the total
amount of donors. It may range from 50 to 85% by mol or from 65 to
80% by mol. The 1,3-diether may constitute the remaining
amount.
[0094] The alkyl-Al compound (b) may be chosen among the trialkyl
aluminum compounds such as for example triethylaluminum,
tri-n-hexylaluminum, tri-n-octylaluminum. It may also be possible
to use mixtures of trialkylaluminum's with alkylaluminum halides,
alkylaluminum hydrides or alkylaluminum sesquichlorides such as
AlEt2Cl and Al2Et3Cl3.
[0095] External electron-donor compounds include silicon compounds,
ethers, esters such as ethyl 4-ethoxybenzoate, amines, heterocyclic
compounds and particularly 2,2,6,6-tetramethyl piperidine, ketones
and the 1,3-diethers. Another class of external donor compounds
include silicon compounds of formula Ra5Rb6Si(OR7)c, where a and b
are integer from 0 to 2, c is an integer from 1 to 3 and the sum
(a+b+c) is 4; R5, R6, and R7, are alkyl, cycloalkyl or aryl
radicals with 1-18 carbon atoms optionally containing heteroatoms.
Methylcyclohexyldimethoxysilane, diphenyldimethoxysilane,
methyl-t-butyldimethoxysilane, dicyclopentyldimethoxysilane,
2-ethylpiperidinyl-2-t-butyldimethoxysilane and 1,1,
1,trifluoropropyl-2-ethylpiperidinyl-dimethoxysilane and
1,1,1,trifluoropropyl-metil-dimethoxysilane may also be silicon
compounds that can be used. The external electron donor compound
may be used in such an amount to give a molar ratio between the
organo-aluminum compound and said electron donor compound of from 5
to 500, alternatively from 5 to 400 or from 10 to 200.
[0096] The catalyst forming components can be contacted with a
liquid inert hydrocarbon solvent such as, e.g., propane, n-hexane
or n-heptane, at a temperature below about 60.degree. C. and from
about 0 to 30.degree. C. for a time period of from about 6 seconds
to 60 minutes.
[0097] The above catalyst components (a), (b) and optionally (c)
can be fed to a pre-contacting vessel, in amounts such that the
weight ratio (b)/(a) is in the range of 0.1-10 and if the compound
(c) is present, the weight ratio (b)/(c) is weight ratio
corresponding to the molar ratio as defined above. The said
components are pre-contacted at a temperature of from 10 to
20.degree. C. for 1-30 minutes. The precontact vessel may be a
stirred tank reactor.
[0098] The precontacted catalyst is then fed to a prepolymerization
reactor where a prepolymerization step takes place. The
prepolymerization step can be carried out in a first reactor
selected from a loop reactor or a continuously stirred tank
reactor, and is generally carried out in liquid-phase. The liquid
medium comprises liquid alpha-olefin monomer(s), optionally with
the addition of an inert hydrocarbon solvent. Said hydrocarbon
solvent can be either aromatic, such as toluene, or aliphatic, such
as propane, hexane, heptane, isobutane, cyclohexane and
2,2,4-trimethylpentane. The amount of hydrocarbon solvent, if any,
is lower than 40% by weight with respect to the total amount of
alpha-olefins or alternatively lower than 20% by weight. Said step
(a) may be carried out in the absence of inert hydrocarbon
solvents.
[0099] The average residence time in this reactor may range from 2
to 40 minutes or alternatively from 10 to 25 minutes. The
temperature may range between 10.degree. C. and 50.degree. C. or
alternatively between 15.degree. C. and 35.degree. C. Adopting
these conditions allows a pre-polymerization degree in the range
from 60 to 800 g per gram of solid catalyst component or
alternatively from 150 to 500 g per gram of solid catalyst
component. Step (a) may further be characterized by a low
concentration of solid in the slurry, in the range from 50 g to 300
g of solid per liter of slurry.
[0100] The polymerization process can be carried out in gas phase
and/or in liquid phase, in continuous or batch reactors, such as
fluidized bed or slurry reactors. For example, it may be possible
to carry out the polymerization of the propylene polymer (A) in
liquid phase, using liquid propylene as diluent, while the
copolymerization stage to obtain the propylene copolymer fraction
(B) can be carried out in gas phase, without intermediate stages
except for the partial degassing of the monomers. Alternatively,
the sequential polymerization stages can be carried out in gas
phase. The reaction time, temperature and pressure of the
polymerization steps are not necessarily critical, and the
temperature for the preparation of fraction (A) and (B), that can
be the same or different, may be from 50.degree. C. to 120.degree.
C. The polymerization pressure may range from 0.5 to 12 MPa if the
polymerization is carried out in gas-phase. The catalytic system
can be pre-contacted (pre-polymerized) with small amounts of
olefins. The molecular weight of the propylene polymer composition
may be regulated by using regulators, such as hydrogen.
[0101] In the second stage of the polymerization process, the
propylene/ethylene copolymer (B) is produced in a conventional
fluidized-bed gas-phase reactor in the presence of the polymeric
material and the catalyst system coming from the preceding
polymerization step. The propylene polymer compositions of the
present disclosure can also be obtained by separately preparing the
said copolymers (A) and (B), operating with the same catalysts and
under the same polymerization conditions as previously illustrated
and subsequently mechanically blending said copolymers in the
molten state using mixing apparatuses, like twin-screw
extruders.
[0102] The polyolefin composition used for the containers of the
present disclosure may further comprise additives employed in the
polyolefin field, such as antioxidants, light stabilizers,
nucleating agents, antiacids, colorants and fillers.
[0103] According to another aspect, the present disclosure relates
to a process for the preparation of a container, which process
comprises injection molding a polyolefin composition according to
the present disclosure.
[0104] The following examples are given to illustrate and not to
limit the present disclosure.
EXAMPLES
[0105] The data of the propylene polymer materials were obtained
according to the following methods:
[0106] Melt Flow Rate
[0107] Determined according to ISO 1133 (230.degree. C., 2.16
kg).
[0108] Ethylene Content of the Polymers (C2 Content)
[0109] Ethylene content has been determined by FT-IR spectroscopy.
The sample of a pressed film has been prepared according to ASTM
D5576-00 (2013).
[0110] The spectrum of a pressed film of the polymer was recorded
in absorbance vs. wavenumbers (cm-1). The following measurements
were used to calculate C2 content:
[0111] a) Area (At) of the combination absorption bands between
4482 and 3950 cm-1 which is used for spectrometric normalization of
film thickness.
[0112] b) Area (AC2) of the absorption band due to methylenic
sequences (CH2 rocking vibration) after a proper digital
subtraction of an isotactic polypropylene (IPP) reference spectrum.
The range 660 to 790 cm-1.
[0113] The ethylene content of component B) has been calculated
according to the following equation:
C2tot=X1C2A+X2C2B
[0114] Wherein C2tot was the total ethylene content; C2A was the
ethylene content of component A; C2B was the ethylene content of
component B) and X1 and X2 were the fraction of components A and B
(X1+X2=1).
[0115] Molar Ratios of the Feed Gases
[0116] Determined by gas-chromatography.
[0117] Samples for the Mechanical Analysis
[0118] Samples have been obtained according to ISO 1873-2:2007
excepting for the flexural modulus for which ISO 3167 has been
used.
[0119] Flexural Modulus
[0120] Determined according to ISO 178.
[0121] Haze (on 1 mm Plaque)
[0122] According to the method used, 5.times.5 cm specimens were
cut from molded plaques of 1 mm thick and the haze value was
measured using a Gardner photometric unit connected to a Hazemeter
type UX-10 or an equivalent instrument having G.E. 1209 light
source with filter "C". Reference samples of known haze were used
for calibrating the instrument. The plaques to be tested were
produced according to the following method.
[0123] 75.times.75.times.1 mm plaques were molded with a GBF
Plastiniector G235190 Injection Molding Machine, 90 tons under the
following processing conditions:
[0124] Screw rotation speed: 120 rpm
[0125] Back pressure: 10 bar
[0126] Melt temperature: 260.degree. C.
[0127] Injection time: 5 sec
[0128] Switch to hold pressure: 50 bar
[0129] First stage hold pressure: 30 bar
[0130] Second stage pressure: 20 bar
[0131] Hold pressure profile: First stage 5 sec
[0132] Second stage 10 sec
[0133] Cooling time: 20 sec
[0134] Mold water temperature: 40.degree. C.
[0135] Melting Temperature, Melting Enthalpy and Crystallization
Temperature
[0136] Determined by differential scanning calorimetry (DSC). A
sample weighting 6.+-.1 mg, was heated to 220.+-.1.degree. C. at a
rate of 20.degree. C./min and kept at 220.+-.1.degree. C. for 2
minutes in nitrogen stream and it was thereafter cooled at a rate
of 20.degree. C./min to 40.+-.2.degree. C., and kept at this
temperature for 2 min to crystallize the sample. Then, the sample
was again heated at a temperature rise rate of 20.degree. C./min up
to 220.degree. C..+-.1. The melting scan was recorded, a thermogram
was obtained, and, from this, melting temperatures was read.
[0137] Xylene Soluble and Insoluble Fractions at 25.degree. C.
(Room Temperature)
[0138] 2.5 g of polymer and 250 cm3 of xylene were introduced in a
glass flask equipped with a reflux condenser and a magnetic
stirrer. The temperature was raised in 30 minutes up to the boiling
point of the solvent. The clear solution was then kept under reflux
and stirring for further 30 minutes. The closed flask was then kept
for 30 minutes in a thermostatic water bath at 25.degree. C. for 30
minutes. The so formed solid was filtered on quick filtering paper.
100 cm.sup.3 of the filtered liquid was poured in a previously
weighed aluminum container which was heated on a heating plate
under nitrogen flow, to remove the solvent by evaporation. The
container was then kept in an oven at 80.degree. C. under vacuum
until constant weight was obtained. The weight percentage of
polymer soluble in xylene at room temperature was then calculated.
The percent by weight of polymer insoluble in xylene at room
temperature was considered the Isotacticity Index of the polymer.
This value corresponds to the Isotacticity Index determined by
extraction with boiling n-heptane, which by definition constitutes
the Isotacticity Index of polypropylene.
[0139] Intrinsic Viscosity (I.V.)
[0140] Determined in tetrahydronaphthalene at 135.degree. C.
[0141] IZOD Impact Strength
[0142] Determined according to ISO 180/1A
Example 1 and Comparative Examples 2-3
[0143] Preparation of the Solid Catalyst Component
[0144] Into a 2000 mL five-necked glass reactor, equipped with
mechanical stirrer, reflux condenser, and a thermocouple, purged
with nitrogen, 1000 mL of TiCl4 were introduced and the reactor
cooled at -5.degree. C. While stirring, 60.0 g of microspheroidal
MgCl2.1.7C2H5OH having average particle size of 58 .mu.m (prepared
in accordance with the method described in example 1 of EP728769)
was added at -5.degree. C. The temperature was raised at 40.degree.
C. and an amount of diethyl 2,3-diisopropylsuccinate such as to
have a Mg/succinate molar ratio of 13 was added. The temperature
was raised to 100.degree. C. and kept at this value for 60 min.
After that the stirring was stopped for 15 min and the solid
settled down. The liquid was siphoned off. After siphoning, fresh
TiCl4 and an amount of 9,9-bis(methoxymethyl)fluorene was added to
have a Mg/diether molar ratio of 26. Then the temperature was
raised to 110.degree. C. and kept for 30 minutes under stirring.
The reactor was then cooled at 75.degree. C. and the stirrer was
stopped for 15 min. After sedimentation and siphoning, fresh TiCl4
was added. Then the temperature was raised to 90.degree. C. and the
suspension was stirred for 15 min. The temperature was then
decreased to 75.degree. C. and the stirrer was stopped, for 15 min.
After sedimentation and siphoning, the solid was washed six times
with anhydrous hexane (6.times.1000 ml) at 60.degree. C. and one
time with hexane at 25.degree. C. The solid was dried in a rotary
evaporator.
[0145] Preparation of the Catalyst System
[0146] Before introducing it into the polymerization reactors, the
solid catalyst component described above was contacted with
aluminum-triethyl (TEAL) and dicyclopentyl-dimethoxysilane (DCPMS)
at a temperature of 15.degree. C.
[0147] Prepolymerization
[0148] The catalyst system was then subject to prepolymerization
treatment at 20.degree. C. by maintaining it in suspension in
liquid propylene for 9 minutes before introducing it into the
polymerization reactor.
[0149] Polymerization
[0150] The polymerization runs were conducted continuously in a
series of two reactors equipped with devices to transfer the
product from one reactor to the one immediately next to it. The
first reactor was a polymerization apparatus as described in EP 1
012 195.
[0151] The catalyst was sent to the polymerization apparatus that
comprises two interconnected cylindrical reactors, riser and
downcomer. Fast fluidization conditions were established in the
riser by recycling gas from the gas-solid separator. The obtained
product was then fed to a fluid bed gas phase reactor. Hydrogen was
used as molecular weight regulator.
[0152] Component (A) was prepared in the first reactor, while
component (B) is prepared in the second reactor.
[0153] Hydrogen was used as molecular weight regulator.
[0154] The gas phase (propylene, ethylene and hydrogen) was
continuously analyzed via gas-chromatography.
[0155] At the end of the run the powder was discharged and dried
under a nitrogen flow.
[0156] The main polymerization conditions are reported in Table
1.
TABLE-US-00001 TABLE 1 Example Comp ex 2 ex 1 Comp ex 3 Component
A) (reactor MZCR) TEAL/external donor wt/wt 6 6 5 TEAL/catalyst
wt/wt 6 6 4 Temperature .degree. C. 73 73 73 Pressure bar-g 27 27
27 Split riser wt % 40 40 40 holdup downcomer wt % 60 60 60
C.sub.3.sup.- riser mole % 80 80 80 C.sub.2.sup.- riser mole % 1.3
1.3 1.2 H.sub.2/C.sub.3.sup.- riser mol/mol 0.028 0.03 0.035
C.sub.2.sup.-/(C.sub.2.sup.- + C.sub.3.sup.-) mol/mol 0.016 0.015
0.015 Component B (gas phase reactor) Temperature .degree. C. 75 75
75 Pressure MPa 18 19 20 C.sub.2.sup.-/C.sub.2.sup.- +
C.sub.3.sup.- mol/mol 0.22 0.21 0.21 H.sub.2/C.sub.2.sup.- mol/mol
0.14 0.35 0.35 H.sub.2 hydrogen, C.sub.2.sup.- ethylene
C.sub.3.sup.- propylene
[0157] The polyolefin composition of example 1 and comparative
examples 2 and 3 have been extruded under nitrogen atmosphere in a
twin screw extruder, at a rotation speed of 250 rpm and a melt
temperature of 200-250.degree. C. with the additives reported in
table 2 and pelletized. The polymers features are reported in table
3
TABLE-US-00002 TABLE 2 Example Comp ex 2 ex 1 Comp ex 3 Glycerol
Monostearate 90 wt % 0.09 0.09 0.09 Irganox 1010 wt % 0.05 0.05
0.05 Irgafoss 168 wt % 0.10 0.10 0.10 Calcium stearate wt % 0.05
0.05 0.05 Millad 3988 wt % 0.18 0.18 0.18
TABLE-US-00003 TABLE 3 Example Comp ex 2 ex 1 Comp ex 3 Component
a) Copolymer content % 87 85 87 Ethylene content wt % 2.3 2.5 2.6
MFR g/10' 20 23 40 Xylene soluble at 25.degree. C. wt % 4.5 5.3 4.8
Component b) Copolymer content wt % 13 15 13 Ethylene content in wt
% 38 27 32 component b) Property of the composition Xylene soluble
at 25.degree. C. wt % 15.9 17.4 15.6 MFR g/10' 18 26 37 XSIV
(intrinsic dl/g 1.56 1.10 1.10 viscosity of XS) Flexural Modulus
MPa 850 850 930 Izod impact at 23.degree. C. KJ/m.sup.2 6.1 10.5
4.9 D/B TT .degree. C. -10.0 -10.6 1.0 HAZE (1 mm plaque) % 86 36
37 Elongation @ break % 680 >720 580 Melting temperature
.degree. C. 152.1 151.3 151.8
* * * * *